This invention relates to an air mixing damper apparatus and an air conditioning apparatus for vehicles, and in particular, relates to an air mixing damper apparatus and an air conditioning apparatus for vehicles which can linearly alter the temperature of the discharged air by operation of a lever of an actuator driving an air mixing damper.
As is well known, an air conditioning apparatus for vehicles incorporates an inside air/outside air box comprising an inside/outside air switching damper that selectively switches introduced air to either inside air or outside air, a blower unit having a blower fan for circulating the introduced air, a cooler unit incorporating an evaporator for exchanging heat between a refrigerant and the introduced air passing therethrough, and an air conditioning unit having a heater unit.
The heater unit generally has a heater core inside a heater unit case for heating the introduced air passing therethrough, an air mixing damper apparatus for regulating the flow volume of the introduced air passing through the heater core, and a plurality of air outlets opening from the heater unit case and respectively provided with dampers.
With the air mixing damper apparatus, a plate door type air mixing damper for opening and closing an air introducing face of the heater core is connected by a link to a rotation type lever of an actuator for driving the air mixing damper. When an occupant operates a lever or the like used for setting the temperature, on the control panel provided within the vehicle compartment, the actuator is driven and the actuator lever rotates and by way of the link, starts the operation of the air mixing damper. The opening of the air mixing damper adjusts the amount of introduced air passing through the heater core and also adjusts the temperature of the discharged air.
That is to say, in the fully closed position with the air intake face of the heater core closed off, cold air from an evaporator located upstream thereof is supplied in its unchanged state as discharged air, and with an increase in opening of the air mixing damper the amount of air to be introduced passing through the heater core increases so that the temperature of the discharged air rises. When the air mixing damper is in a fully opened position, for example all of the cold air from the evaporator is passed through the heater core so that the temperature of the discharged air is increased.
However, in the case of the aforementioned conventional air mixing damper apparatus, at the time when the air mixing damper starts to open and at the time when the opening is completed, that is, during the interval that the air mixing damper is opened from a fully closed to a slightly opened position, and during the interval from a little before the fully open position through to a fully opened position, there is a problem that, compared to other positions, the temperature changes at these times is severe. That is to say, looking at FIG. 17 showing the relationship between the opening of the air mixing damper and the temperature of the discharged air, the change in temperature corresponding to movement of the actuator lever is extremely sharp at the initial opening stage where the opening of the air mixing damper is slight, and at the final opening stage where the air mixing damper is at a little before the fully open position through to the fully opened position.
This kind of phenomenon is a problem which generally arises in cases where the air mixing damper is linearly rotated together with an actuator lever. To explain simply, this is because at the time when the air mixing damper starts opening and when opening is completed it responds sensitively, and at other times when it is opened midway the response is slow.
Accordingly, if in this way it is not possible to obtain a linear change in the temperature of the discharged air with respect to the operation of an actuator lever, that is, with respect to operation by an occupant, instances arise in which it is not possible to achieve air conditioning as intended by the occupant.
For the purpose of counteracting this, it has been considered to drive the actuator so that it rotates slowly at times when the air mixing damper is starting to open and when it completes opening. However there is a problem in that such an improvement to the actuator is accompanied by higher costs.
Further, the provision of a baffle has also been considered in order to effect an appropriate change in temperature. However, there is a problem in that a decrease in air volume as a result of a baffle is unavoidable.
Accordingly the present invention provides an air mixing damper apparatus and an air conditioning apparatus for vehicles where the temperature of the discharged air can be changed linearly with respect to the operation of an actuator lever.
In order to resolve the abovementioned problems, a first aspect of the present invention is an air mixing damper apparatus characterized in that there is provided between a plate door type air mixing damper for opening and closing an air introducing face of a heater core, and a rotation type lever of an actuator for driving the air mixing damper, a mechanism for adjusting rotational speed of the air mixing damper to linearly change the temperature of discharged air with respect to the operation of the lever of the actuator. With such a construction, it becomes possible to linearly change the temperature of the discharged air with respect to the operation of the actuator lever.
A second aspect of the present invention is an air mixing damper apparatus characterized in that there is provided between a plate door type air mixing damper for opening and closing an air introducing face of a heater core, and a rotation type lever of an actuator for driving the air mixing damper, a mechanism for adjusting rotational speed at an initial opening stage and a final opening stage of the air mixing damper, to a speed lower than at an intermediate opening stage. With such a construction, it becomes possible to lower the change amount with respect to the movement of the actuator lever at the initial opening stage and the final opening stage of the air mixing damper, to a less than at the intermediate opening stage.
With a third aspect of the present invention, an air mixing damper apparatus of the first or second aspects is characterized in that the mechanism for adjusting rotational speed comprises; a cam provided in the air mixing damper and a pin provided on the lever of the actuator for engaging with the cam. With such a construction, there is no longer a need to improve the actuator.
With a fourth aspect of the present invention, the air mixing damper apparatus of the third aspect is characterized in that the cam incorporates a guide path for guiding the pin of the lever of the actuator, and the guide path has a first guide path for effecting control at an initial opening stage of the air mixing damper, a second guide path for effecting control at an intermediate opening stage of the air mixing damper, and a third guide path for effecting control at a final opening stage of the air mixing damper. With such a construction, it becomes possible to form a first guide path, a second guide path and a third guide path, in accordance with the air mixing damper.
With a fifth aspect of the present invention, the air mixing damper apparatus of the third aspect is characterized in that the cam has an opening portion with a guide path for guiding the pin of the lever of the actuator provided around the periphery thereof, and the guide path has a first guide path for effecting control at an initial opening stage of the air mixing damper, a second guide path for effecting control at an intermediate opening stage of the air mixing damper, and a third guide path for effecting control at a final opening stage of the air mixing damper. With such a construction, it becomes possible to form, for example, a first guide path, a second guide path and a third guide path in accordance with the air mixing damper.
With a sixth aspect of the present invention, the air mixing damper apparatus of the fourth or fifth aspects is characterized in that the first guide path is formed in a direction gradually separating outward with respect to a turning path of the pin of the lever of the actuator, in a fully closed position of the air mixing damper, and the third guide path is formed in a direction gradually separating outward with respect to the turning path of the pin of the lever of the actuator, in a fully open position of the air mixing damper. With such a construction, in the initial opening stage of the air mixing damper, when the air mixing damper starts to open from a fully closed position, it is possible to operate in such a way that it opens gradually. Moreover, in the final opening stage of the air mixing damper, it is also possible to operate in such a way that it opens gradually during the interval between a near fully opened position and a fully opened position.
With a seventh aspect of the present invention, the air mixing damper apparatus of the fifth or the sixth aspects is characterized in that there is provided an urging device for urging the pin of the lever of the actuator into the first guide path at least at an initial opening stage of the air mixing damper, and urging the pin of the lever of the actuator into the third guide path at least at a final opening stage of the air mixing damper. With such a construction, it becomes possible to positively guide the pin of the actuator lever in at least the first guide path and the third guide path.
With an eighth aspect of the present invention, the air mixing damper apparatus of any one of the second through seventh aspects is characterized in that the range of the opening of the air mixing damper is from fully closed to around 15 degrees in the initial opening stage, while the range of the opening of the air mixing damper is from 20 degrees from fully open to fully open in the final opening stage.
A ninth aspect of the present invention is an air conditioning apparatus for vehicles having an air conditioning unit provided with: an inside air/outside air box incorporating an inside/outside air switching damper for opening an outside air introducing inlet and an inside air introducing inlet to selectively switch introduced air to one of inside air and outside air, a blower unit having a blower fan for blowing the introduced air, a cooler unit fitted with an evaporator for exchanging heat between a refrigerant and the introduced air passing therethrough, and a heater unit having a heater core provided inside a heater unit case for heating the introduced air passing therein, an air mixing damper apparatus for adjusting the flow quantity of the introduced air which passes through the heater core, and a plurality of air outlets opening from the heater unit case and respectively provided with dampers, characterized in that the air mixing damper apparatus is an air mixing damper apparatus according to any one of the first through eighth aspects. With such a construction, it becomes possible to linearly change the temperature of the discharged air in accordance with the operation of temperature adjustment of the discharged air by an occupant.
A tenth aspect of the present invention is an air mixing damper apparatus provided with a plate door type air mixing damper for opening and closing an air introducing face of a heater core, and an operating device for specifying an operating amount of the air mixing damper, characterized in that an operating amount of the air mixing damper with respect to an operating amount of the operating device changes from operation initiation to operation completion. With such a construction, it becomes possible to stabilize the change in the temperature of the discharged air in accordance with the operation by an occupant of temperature adjustment of the discharged air.
With an eleventh aspect of the present invention, the air mixing damper apparatus of the tenth aspect is characterized in that an operating amount of the air mixing damper with respect to an operating amount of the operating device at operation initiation and operation completion is small compared to at an intermediate operation stage. With such a construction, it becomes possible to linearly change the temperature of the discharged air in accordance with the operation by an occupant of temperature adjustment of the discharged air.